The genus Sphacelaria Lyngbye (Phaeophyceae) in the Netherlands

The species of the genus Sphacelaria Lyngb. that occur in the Netherlands have been investigated. These species are: S. plumigera Holmes, S. radicans (Dillw.) Ag., S. fusca (Huds.) Ag. It is suggested that S. furcigera and S. saxatilis should be regarded as synonyms of S. fusca. It was found that S. fusca also forms bifurcate propagulae in contrast to reports in the literature. Cultures were grown of S. plumigera, S. fusca, S. britannica, and S. radicans. The cultures of S. fusca, S. britannica, and S. radicans exhibited very feebly fixed polarity in contrast to the cultures of S. plumigera. S. cirrosa and S. fusca are considered to be two different species.